ORBIT, EYE & LACRIMAL APPARATUSPART-I

BY

LECTURER

FARIS MUHAMMED AL-HADDAD

M.B.CH.B, F.I.B.M.S ( ANATOMY )

DEPARTMENT OF ANATOMY, COLLEGE OF MEDICINE,

HAWLER MEDICAL UNIVERSITY

ORBIT & EYE

• THE EYE IS THE ORGAN OF VISION & THE PRINCIPLE COMPONENT OF THE VISUAL APPARATUS.

• THE EYE IS LODGED IN THE ORBIT, TOGETHER WITH THE EXTRAOCULAR MUSCLES WHICH MOVE THE EYE, NERVES, LACRIMAL GLAND, FASCIA AND FAT.

BONY SKELETON OF THE ORBIT

THE ORBIT

• A PYRAMIDAL BONY CAVITY

Its lying on its side, having :

1. Apex : is at the back

2. Base : forming the orbital margin on the front of the facial skeleton

ORBITAL MARGIN BONES

SUPERIORFRONTAL BONE

LATERAL PROCESSES OF FRONTAL & ZYGOMATIC BONES

INFERIOR ZYGOMATIC & MAXILLARY BONES

MEDIAL PROCESSES OF FRONTAL & MAXILLARY BONES

ORBITAL WALL BONE

ROOFFRONTAL BONE (ORBITAL PLATE)

LATERAL 1. ZYGOMATIC BONE2. SPHENOID BONE

(GREATER WING)

FLOOR MAXILLARY BONE (ORBITAL PLATE)

MEDIAL(FROM BEFORE BACKWARDS)

1. MAXILLARY BONE (FRONTAL PROCESS)2. LACRIMAL BONE3. ETHMOID BONE (ORBITAL PLATE)4. SPHENOID BODY

OPENINGS IN THE ORBIT POSITION TRANSMITS

ORBITAL OPENING ANTERIORLY 1/6TH OF EYES ARE EXPOSED

SUPRAORBITAL NOTCH ( OR FORAMEN )

SUPRAORBITAL MARGIN SUPRAORBITAL N. & B.V.s

INFRAORBITAL GROOVE & CANAL

ORBITAL PLATE OF MAXILLA ( FLOOR OF ORBIT )

INFRAORBITAL N.( A CONOTINUATION OF MAXILLARY N. )

& B.V.s

NASOLACRIMAL CANALANTERIORLY ON MEDIAL

WALL OF ORBIT NASOLACRIMAL DUCT TO THE INFERIOR

MEATUS OF THE NOSE

OPENINGS IN THE ORBIT

POSITIONTRANSMITS

INFERIOR ORBITAL FISSURE

POSTERIORLY BETWEEN : • MAXILLA • GREATER WING OF

SPHENOID

• MAXILLARY N. & ITS ZYGOMATIC BR. • INFERIOR OPHTHALMIC VEIN • SYMPATHETIC N.s ( IOF COMMUNICATES WITH PTERYGO –PALATINE FOSSA)

OPTIC CANAL POSTERIORLY IN : • LESSER WING OF

SPHENOID

• OPTIC N. • OPHTHALMIC A.(THIS CANAL CMMUNICATES WITH MIDDLE CRANIAL FOSSA)

OPENING INTHE ORBIT

LOCATION TRANSMITS

SUPERIOR ORBITAL FISSURE

POSTERIORLY BETWEEN : • GREATER WING • LESSER WING

OF SPHENOID

UPPER LATERAL PART ABOVE TENDENOUS RING :• LACRIMAL N. • FRONTAL N.s• 4TH C.N.• SUPERIOR OPHTHALMIC VEIN

MIDDLE PART THROUGH THE RING :• UPPER DIVISION OF 3RD C.N.• NASOCILIARY N.• LOWER DIVISION OF 3RD C.N.• ABDUCENT N.

LOWER MEDIAL PART BELOW THE TENDENOUS RING :• INFERIOR OPHTHALMIC VEIN

FASCIA OF THE ORBIT

ORBITAL FASCIA

• IS PERIOSTEUM

• LOOSELY ATTACHED TO BONES

• CONTINUOUS THROGH THE OPENINGS & FISSURE WITH PERIOSTEUM COVERING OTHER BONES

• ORBITALIS MUSCLE : IS A THIN LAYER OF SMOOTH M., THAT BRIDGES THE INFERIOR ORBITAL FISSURE, IS OF UNKNOWN FUNCTION.

FASCIAL SHEATH OF THE EYEBAL *

• SURROUND EYE BALL FROM OPTIC N. TO CORNEOSCLERAL JUNCTION

• SEPARATES EYEBALL FROM SURROUNDING FAT

• PROVIDES A SOCKET FOR FREE MOVEMENT

• PERFORATED BY TENDONS OF OCULAR M.s & ENSHEATHES THESE M.s

*

• THE SHEATHES OF THE MEDIAL & LATERAL RECTI ARE ATTACHED TO THE MEDIAL & LATERAL WALLS OF THE ORBIT BY THE TRIANGULAR MEDIAL & LATERAL CHECK LIGAMENTS

• THE LOWER PART OF THE SHEATH WHICH PASSES BENEATH THE EYEBALL & CONNECTING CHECK LIGAMENTS IS THICKENED & SUSPENDS THE EYEBALL, ITS CALLED SUSPENSORY LIGAMENT OF THE EYE

NEUROVASCULATURE OF THE ORBIT

NERVE OF ORBIT

ENTERSORBIT

THROUGHORIGIN COURSE IN ORBIT ACTION NOTES

OPTIC N. OPTIC CANAL

RETINAL GANGLION

CELLS

• OPHTHALMIC A. : FIRST LATERAL TO OPTIC N., THEN CROSS OVER IT FROM LATERAL TO MEDIAL

• OPTIC N. RUNS ANTERO -LATERALLY WITHIN CONE OF RECTI M.s

• OPTIC N. PEIRCES SCLERA MEDIAL TO POSTERIOR EYE POLE

• OPTIC N. IS SURROUNDED BY THE THREE MENINGIES, SO C.S.F. IN THE SUBARACH-NOID SPACE REACHES AS FAR AS THE SCLERA.

CONVEYS VISUAL

INFORMA -TION FROM

EYES

A RISE IN C.S.F. PRESSURE IS

TRANSMITTED TO THE BACK OF

THE EYE BY OPTIC N.

LEADING TO PAPILLOEDEMA

NERVE OF ORBIT

ENTERSORBIT

THROUGHORIGIN COURSE IN ORBIT ACTION

LACRIMAL N. UPPER PART OF THE

SUPERIOR ORBITAL FISSURE

OPHTHALMIC DIVISION OF TRIGEMINAL

N.

• PASSES FORWARDS ALONG THE UPPER BORDER OF THE LATERAL RECTUS M.

• ITS JOINED BY A BRANCH OF ZYGOMATICOTEMPORAL N. WHICH ENTERS LACRIMAL GLAND (PARASYMPATHETIC SECRETOMOTOR FIBERS )

• CONVEYSPARASYMPATHETIC SECRETO-MOTOR FIBERS TO LACRIMAL GL.

• SUPPLIES UPPER CONJUNCTIVAL FORNIX

• SUPPLIES SKIN OF UPPER EYE LID

*

*

NERVE OF ORBIT

ENTERSORBIT

THROUGHORIGIN COURSE IN ORBIT ACTION

FRONTAL N. UPPER PART OF SUPERIOR

ORBITAL FISSURE

OPHTHALMIC DIVISION OF

TRIGEMINAL N.

• PASSES FORWARDS ON THE SUPERIOR SURFACE OF LEVATOR PALPEBRAE SUPERIORIS.

• DIVIDE IN TO :

1. SUPRAORBITAL N.2. SUPRATROCHLEAR N.

1. BOTH SUPRAORBITAL & SUPRATROCHLEAR N.s WIND AROUND THE UPPER MARGIN OF THE ORBITAL CAVITY TO SUPPLY THE SKIN OF THE FOREHEAD

2. SUPRATROCHLEAR N. ALSO SUPPLIES THE MUCOUS MEMBRANE OF THE FRONTAL AIR SINUS

NERVE OF ORBITENTERSORBIT

THROUGHORIGIN

COURSE IN THE ORBIT

OCCULOMOTOR N. (**)

S.O.F MIDBRAIN

• SUPERIOR RAMUS : SUPPLIES /1. SUPERIOR RECTUS M.2. LEVATOR PALPEBRAE SUPERIORIS M.

• INFERIOR RAMUS : SUPPLIES /1. INFERIOR RECTUS M.2. MEDIAL RECTUS M.3. INFERIOR OBLIQUE M. ( GIVES OFF A BRANCH TO

CILLIARY GANG. CARRYING PARASYMPATHETIC SUPPLY TO SPHINCTER PUPILLAE & CILLIARY M.s)

**

NERVE OF ORBITENTERS ORBIT

THROUGHORIGIN COURSE IN ORBIT

NASOCILIARY N.(*)

TENDEOUS RING OF THE SUPERIOR

ORBITAL FISSURE

OPHTHALMIC DIVISION OF

TRIGEMINAL N

• CROSSES OPTIC N. • RUNS ALONG UPPER

MARGIN OF MEDIAL RECTUS M.

BRANCHES OF NASOCILIARY N.

1. COMMUNICATING

BR. TO CILIARY GANG.

2.LONG CILIARY

3.POSTERIOR ETHMOIDAL

4. INFRATROCHLEAR 5. ANTERIOR ETHMOIDAL

• A SENSORY N.• SENSTION FROM

EYE TRANSMITTED TO CILIARY G. BY SHORT CILIARY AND TO NASOCILIARY N. BY LONG CILIARY N.

• 2-3 IN NUMBER• CONTAINS SYMP-

ATHETIC FIBERS FOR DIALTOR PUPILLAE M. OF THE IRIS.

• PASSES FORWARDS TO SCLERA & CONTINUE BETWEEN SCLERA & CHOROID TO REACH TO THE IRIS

SUPPLIES :• ETHMOIDAL AIR

SINUS• SPHENOIDAL AIR

SINUS

• PASSES FORWARDS BELOW THE PULLEYOF THE SUPERIOR OBLIQUE M.

• SUPPLIES THE SKIN OF THE MEDIAL PART OF THE UPPER EYE LID AND ADJACENT NOSE.

• PASS THROUGH ANTERIOR ETHMO-IDAL FORAMEN

• ENTERS ANTERIOR CRANIAL FOSSA ON UPPER SURFACE OF CRIBRIFORM PLATE.

• ENTERS NASAL CAVITY THROUGH SLIT IN CRISTA GALI

• APPEARS IN FACE AS EXT. NASAL BR.

*1

23

4

5

NASOCILIARY N.

ANT.

POST.

ETHMOIDAL N.

INFRATROCHLEAR N.

LONG CILIARY N.

COMMUNICATING BR. TO CILIARY GANG

NERVE OF ORBIT

ENTERS ORBIT THROUGH

ORIGIN ACTION

1. TROCHLEAR N. UPPER PART OF

S.O.F.MIDBRAIN SUPPLIES SUPPERIOR OBLIQUE

2. ABDUCENT N. LOWER PART OF

S.O.F.PONTOMEDULLARY

JUNCTIONSUPPLIES LATERAL RECTUS

1.2.

CILIARY GANGLION (*)

DEFINITION A PARASYMPATHETIC GANGLION

LOCATION POSTERIOR PART OF THE ORBIT

PREGANGLIONIC FIBERSRECEIVED FROM OCCULOMOTOR N. ( THROUGH ITS N. TO INF. OBLIQUE

M.)

POSTGANGLIONIC FIBERS

LEAVES THE GANG. TO THE SHORT CILIARY N.s ENTERS THE EYE BALL

SUPPLYING SPHINCTER PUPILLAE M. & CILIARIS M.

** A NUMBER OF SYMPATHETIC FIBERS PASSES FROM INTERNAL CAROTID PLEXUS INTO THE ORBIT THROUGH THE CILIARY GANG. WITHOUT INTERRUPTION

*

OPHTHALMIC ARTERY

ORIGIN A BRANCH OF INTERNAL CAROTID A. AFTER EMERGING FROM CAVERNUS SINUS

ENTERS THE ORBIT THROUGH OPTIC CANAL WITH OPTC N.

COURSE IN ORBIT RUNS FORWARDS, CROSSES THE OPTIC N.FROM LATERAL TO MEDIAL WALL OF ORBIT

BRANCHESOF OPHTH -ALMIC A.

1. CENTRAL A. OFRETINA

• PIERCES THE MENIGIES OF OPTIC N. • ENTERS & RUNS IN THE OPTIC N. TO

REACH THE EYE BALL AT THE CENTER OF OPTIC DISC.• DIVIDES INTO END ARTERIES SUPPLYING THE RETINA

2. MUSCULAR BR.s -

3. CILIARY A.s• ANTERIOR : SUPPLY EYE BALL AT CORNEOSCLERAL JUNC.• POSTERIOR : ENTERS OPTIC N.

4. LACRIMAL A. SUPPLIES LACRIMAL GLAND

5.SUPRAORBITAL & 6.SUPRATROCHLEAR A.s

-

SUPRAORBITAL BR.

SUPRTROCHLEAR BR.

POSTERIOR CILIARY BR.

OPHTHALMIC A.

LACRIMAL BR.

P.V.P

F.V

1

2C.V

NOTE : NO LYMPHATIC VESSLES ORNODES IN THE EYES

OPHTHALMIC VEINS

1. SUPERIOR OPHTHALMIC VEINS

COMMUNICATES INFRONT WITH

FACIAL VEIN

BOTH VEINS PASS

BACKWARDS THROUGH

S.O.F.

BOTH DRAIN INTO

CAVERNOUS SINUS(C.V.)2.

INFERIOR OPHTHALMIC VEIN

COMMUNICATES WITH

PTERYGOID VENOUS PLEXUS (P.V.P) THROUGH

I.O.F.

MUSCLES OF THE ORBIT

EXTRAOCCULAR MUSCLES OF THE EYE

MUSCLE ORIGIN INSERTION N. SUPPLY

SUPERIORRECTUS

TENDENOUS RING ON THE POSTERIOR WALL OF

THE ORBITAL CAVITY

SUPERIOR SURFACE OF THE EYE BALL JUSTPOSTERIOR TO CORNEOSCLERAL JUNCTION

(JPTCSJ)

CN IIIINFERIOR RECTUS

SAME INFERIOR SURFACE OF THE EYE BALL

(JPTCSJ)

MEDIAL RECTUS

SAME MEDIAL SURFACE OF THE EYE BALL

(JPTCSJ)

LATERAL RECTUS

SAMELATERAL SURFACE OF THE EYE BALL

(JPTCSJ)CN VI

SUPERIOR OBLIQUE

POSTERIOR WALL OF ORBITAL CAVITY

PASSES BENEATH THE PULLEY TO BE ATTACHED TO THE SUPERIOR SURFACE OF THE EYE BALL

BENEATH THE SUPERIOR RECTUSCN IV

INFERIOR OBLIQUE

FLOOR OF ORBITALCAVITY

LATERAL SURFACE OF THE EYE BALL BENEATH THE LATERAL RECTUS

CN III

EXTRAOCCULAR MUSCLE ACTION

SUPERIOR RECTUS RISES CORNEA UP & MEDIALLY

INFERIOR RECTUS DEPRESSES CORNEA DOWN & MEDIALLY

MEDIAL RECTUS ROTATESCORNEA MEDIALLY

LATERAL RECTUS ROTATES CORNEA LATERALLY

SUPERIOR OBLIQUE ROTATES CORNEA INFEROLATERALLY

INFERIOR OBLIQUE ROTATES CORNEA SUPEROLATERALLY

SR

MR

IR

LR

SO

IO

EYELIDS

EYE LIDS

• PROTECTS THE EYES FROM INJURY & EXCESSIVE LIGHT BY THEIR CLOSURE.

• UPPER IS LARGER & MORE MOBILE THAN LOWER LIDS.

• UPPER & LOWER MEET AT MEDIAL & LATERAL ANGLES

• PALPEBRAL FISSURE IS AN ELLEPTICAL OPENING BETWEEN THE LIDS & IS THE ENTRANCE TO THE CONJUNCTIVAL SAC.

MUSLES OF THE EYE LID

MUSCLE ORIGIN INSERTION N. SUPPLY ACTION

LEVATOR PALPEBRAE SUPERIORIS

BACK OF ORBITAL CAVITY

ANTERIOR SURFACE & UPPER MARGIN OF THE

SUPERIOR TARSAL PLATE

• STRIATED :3RD C.N.

• SMOOTH :SYMPATHETIC

RSISES UPPER EYELID

ORBICLARIS OCULI :

1. PALPEBRALPART

2. ORBITAL PART

MEDIAL PALPEBRAL LIG.

MEDIAL PALPEBRAL LIG. & ADJOINING

BONE

LATERAL PALPEBRAL

RAPHAE

LOOPS & RETURN TO ORIGIN

FACIAL N.

FACIAL N.

CLOSES EYE LID & DIALATE LACRIMAL

SAC

PROTECTS EYEBALL

STRUCTURES OF THE EYELID

STRUCTURE DEFINITION

1. SKIN COVERS EYELID SUPERFICIALLY,

2. EYE-LASHESWHICH ARE CURVED HAIR ON FREE EDGE OF EYELID,

ARRANGED IN 2-3 RAWS AT MUCOCUTANE-OUS JUNCTION.

3. GLAND ZEISA SEBACEOUS GL. THAT OPENS DIRECTLY TO THE EYE

LASH FOLLICLES

4. CILIARY GL OF MOLL

MODIFIED SWEAT GL.s THAT OPEN SEPARATELY BETWEEN ADJACEN EYE LASHES

5. TARSAL (MEIBOMIAN) GLANDS

ARE LONG MODIFIED SEBACEOUS GL. THAT POUR THEIR OILY SECRETIONS TO THE MARGIN OF THE LID. THEIR

OPENINGS ARE BEHAND EYE LASHES, PRVENT OVERFLOW OF TEARS & MAKE THE CLOSED EYELIDS

AIRTIGHT

STRUCTURES OF THE EYELID

STRUCTURE DEFINITION

6. LACUS LACRIMALIS SEPARATING THE MEDIAL ANGLE OF

THE EYE LIDS FROM THE EYEBALL

7. CARUNCULA LACRIMALISA REDDISH YELLOISH ELEVATION LIES IN

THE CENTER OF THE LACUS LACRIMALIS

8. PLICA SEMILUNARIS A SEMILUNAR FOLD LIES AT THE

LATERAL SIDE OF THE CARUNCULE

9. PAPILLA LACRIMALISA SMALL ELEVATION ON THE MEDIAL ENDS OF THE EYELID ( MEDIAL ANGLES)

10. PUNCTUM LACRIMLEA SMALL HOLE AT THE SUMMIT OF THE PAPILLA THAT LEADS TO CANALICULUS

LACRIMALIS

6

7

8

9

10

STRUCTURES IN EYELIDS

STRUCTURE DEFINITION

11. COJUNCTIVA

• A MUCOUS MEMBRANE THAT LINES EYE LIDS AND REFLECTED ON THE EYE BALL AS THE SUP. & INF. FORNICES,IT BECOME CONTINU-OUS WITH THAT OF THE CORNEA.

• THE UPPER LATERAL PART OF SUP. FORNIX IS PEIRCED BY THE DUCTS OF THE LACRMAL GL.

• IT FORMS A POTENTIAL SPACE CALLED THE COJUNCTIVAL SAC, WHICH OPENS AT PALPEBRAL FISSURE

12. SUBTARSALSULCUS

• A GROOVE BENEATH THE EYE LID, RUNS CLOSE & PARALLEL TO THE LID MARGIN,

• TRAPPS FOREIGN BODIES ENTERRING CONJUNCTIVAL SAC ( SO ITS IMPORTANT CLIN-ICALLY ).

FRAMEWORK OF EYELID

STRUCTURE DEFINITION

1.ORBITALSEPTUM

A FIBROUS SHEET THAT IS ATTACHED TO THEPERIOSTEUM OF THE ORBITAL MARGINS,

2. TARSAL PLATES

ARE SUP. & INF. THICKENINGS OF THE ORBITAL SEPTUM AT MARGINS OF THE LIDS, TARSAL GL.s ARE EMBEDDED IN THE POSTERIOR SURFCAE OF TARSAL PLATES.

3. LATERAL PALPEBRAL LIGAMENT

A BAND ATTACHES LATERAL ENDS OF TARSAL PLATES TO A BONY TUBERCLE JUST WITHIN ORBITAL MARGIN

4. MEDIAL PALPEBRAL LIGAMENT

A BAND ATTACHES MEDIAL ENDS OF TARSAL PLATES TO LACRIMAL CREST OF THE MEDIAL ORBITAL MARGIN

1

2

1

23 4

1. ORBICULARIS OCULI (PALPEBRAL PART) :

COVERS THE SUPERFICIAL SURFACE OF

THE TARSAL PLATE & ORBITAL SEPTUM.

2. LEVATOR PALPEBRAE SUPERIORIS :

ITS INSERTION APPONEUROSIS PEIRCES

THE ORBITAL SEPTUM TO REACH THE

ANTERIOR SURFACE OF THE SUPERIOR

TARSAL PLATE & SKIN.

2

1

1

LACRIMAL APPARATUS

LACRIMAL APPARATUS

PARTS LOCATION NOTES

1.LACRIMAL GLAND

A. PALPEBRAL ( LARGE ) PART

B. ORBITAL ( SMALL ) PART

ABOVE THE EYE BALL IN ANTERIOR & UP. PART OF ORBIT POSTERIOR TO ORBITAL SEPTUM

• BOTH PARTS ARE CONTINUOUS AROUND THE LATERAL MARGIN OF LEV. PALP. SUP. APPONEUROSIS

• OPENS TO LATERAL PART OF SUP. FORNIX BY 12 DUCTS.

2. LACRIMAL DUCTS

1A. LACUS LACRIMALIS

TEARS ACCUMULATES HERE

2B. PUNCTA LACRIMALIS

THROUGH IT TEARS ENTER L. CANALICULI

3C. LACRIMAL CANALICULI

DIRECTS TEARS MEDIALLY TO L. SAC

4D. LACRIMAL SAC

LACRIMAL GROOVE BEHIND MEDIAL PALPEBRAL LIG.

IT’S THE UPPER BLIND END OF THE NASOLACRIMAL DUCT

5E. NASOLAC-RIMAL DUCT

1.3 CMs FROM LOWER END OF L. SAC DESCENDS DONWARDSIN A BONY CANAL TO OPEN IN INFERIOR MEATUS OF NOSE

6F. LACRIMAL FOLDS

GUARDS THE NLD OPENING IN INF. MEATUS

PREVENT AIR FROM BEING FORCED UP THE N.L.D TO L. SAC DURING BLOWING THE NOSE

Deep petrosal N.